Due to recent trends in energy conservation, environmental energy that does not depend on fossil fuels or the like is routinely attracting attention. Energy generated based on sunlight, wind power, or the like is widely known as environmental energy that has become routine. However, in addition thereto, vibrational energy, thermal energy, electromagnetic waves, osmotic pressure, bioenergy, and the like can also be mentioned.
As a power generation device configured to generate electric power using the above-described environmental energy, a power generation device configured to generate electric power by using vibrational energy has been developed (see, for example, Patent Literature 1). As a means for confirming whether or not power generation is being performed in a power generation device using environmental energy, for example, it is conceivable to directly measure an output of a power generation element with a measuring instrument such as a tester or an oscilloscope. In this case, because the output impedance of the power generation element is high, it is necessary to establish a connection via an impedance conversion circuit in order to use a tester or the like (see, for example, Patent Literature 2).